Final Pot: $3.64.
Opp is loose passive,understands something,he lost to me few big pots,4-6 medium ones in a row,so he started to fold to my cbets or more often to turn bets with weak hands,tried to catch me few tom with tpgk.This time he calls me twice.I understand his range is uber wide on flop and turn and very big part of that range is fd.During hand I thought he can have lot of flushes,sets (big part of his range) and also reasonable part of worst hands.If you consider dynamics between us,his game change Is this a missed valuebet spot? If it is,then what should be bet size ? thin, normal? His AF on river 3, I thought he sometimes can bluff raise thin bet on wet board.
I stoved it later with more reasonable range,maybe to much credit but results are here:
91 games 0.005 secs 18,200 games/sec

Even a fish would have hard time there Calling with a lot worse and as well you mentioned that he somehow started to Call less. Therefore I like often times Check behind in this situation and even not bet value there. Although I'd bet the turn like $1,30-$1,40 or something similar.